package loop

import (
	"context"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/capability/restrict"
)

// SessionEnv is the per-conversation context that gates memory injection and
// extraction for one Run call. It travels on the call's context rather than on
// the shared Loop because Loop is reused across concurrent sessions (every
// channel/group/stranger message resolves its own isolation boundary); storing it
// on the Loop struct would race.
type SessionEnv struct {
	// ActorEnv is the resolved actor environment: owner, group_member, stranger.
	// It is the strongly-typed identity lane decided structurally by the channel
	// layer (design/11 §0), never inferred from prompt text.
	ActorEnv restrict.ActorEnv
	// MemWritable reports whether this conversation may write shared memory. It is
	// true only for the owner's private conversation; group chats and strangers
	// are read-only (design/02 §3, design/11 §2).
	MemWritable bool
	// PersonaID is the role this conversation speaks as (design/22 §2/§4.2), resolved
	// per turn by the caller (normally the gateway's session-binding resolver). Empty
	// means "inherit the loop's configured role" (Options.PersonaID, the global default
	// role), which keeps every pre-multi-character caller — channelbridge, backthink,
	// internal autonomous passes — behaving exactly as before. It scopes the system
	// prompt, the memory namespace, the emotion machine and the thinking budget; it is
	// NOT an identity or permission input: ActorEnv/MemWritable alone decide access
	// (project red line).
	PersonaID string
}

// Restricted reports whether this is a group-chat or stranger conversation, i.e.
// the read-only memory isolation context. Because MemWritable is true only for
// the owner's private conversation, !MemWritable is exactly the restricted set.
func (e SessionEnv) Restricted() bool { return !e.MemWritable }

// OwnerEnv returns the full-access owner session environment (private
// conversation, memory read+write). It is the Web main-session and internal
// automated-task default, matching the pre-existing owner-full behavior. It binds
// no explicit role (PersonaID is empty), so the loop falls back to its configured
// default role — the caller that knows the session's role sets PersonaID on the
// returned value (design/22 §4.2).
func OwnerEnv() SessionEnv {
	return SessionEnv{ActorEnv: restrict.ActorOwner, MemWritable: true}
}

// defaultSessionEnv is the owner-full environment used when a caller attaches no
// explicit env: full memory read and write, the pre-existing behavior.
func defaultSessionEnv() SessionEnv {
	return OwnerEnv()
}

type sessionEnvKey struct{}

// WithSessionEnv attaches env to ctx so Run's memory gates honor the
// group/stranger read-only isolation per call. It is concurrency-safe: the env
// travels with the call's context and is never stored on the shared Loop.
func WithSessionEnv(ctx context.Context, env SessionEnv) context.Context {
	return context.WithValue(ctx, sessionEnvKey{}, env)
}

// sessionEnvFrom returns the env attached to ctx, or the owner-full default when
// none was attached (backward compatible).
func sessionEnvFrom(ctx context.Context) SessionEnv {
	if ctx == nil {
		return defaultSessionEnv()
	}
	if env, ok := ctx.Value(sessionEnvKey{}).(SessionEnv); ok {
		return env
	}
	return defaultSessionEnv()
}